There is increasing interest in using analytical techniques to monitor chemicals in the environment. For example, herbicides in lakes, rivers, ponds, and reservoirs may be monitored to ensure that the water is safe to drink or that it will not endanger the habitat. In many instances, analytical techniques for water will require a relatively large liquid volume (e.g., 100 mL to 1000 mL of liquid) and the sample location can be far from the analytical laboratory. It should be noted that analytical instrumentation such as, for example, high pressure liquid chromatography (HPLC) and capillary chromatography cannot be easily transported to the sample source because they are relatively heavy and delicate instruments. For these reasons, most procedures for sampling remote bodies of water require the collection and shipment of the water samples from the remote site to the laboratory. In addition to the cost and inconvenience of collecting, bottling, preserving, and shipping the water, there are possibilities for cross-contamination and errors at each step in the process.
In an environmental study, water can be monitored for a prolonged period of time. It may not be convenient or cost-effective to have a human operator perform the water sampling process. One possibility is to use a pump can that is configured to extract water from the sample source at a constant flow for a period of time and stored in a container. An issue with using a pump is that it needs to have sufficient power and a uniform flow rate for the entire sampling period. Applicants believe that there is a need for a device and method that can verify that the sample has been collected properly. In addition, Applicants believe that the verification device and method should not require electrical power so that implementation in a remote setting would be easy to use.